Can my dog die if she eats a succulent? He even spent a few extra minutes telling me about scale, how it spreads and what I can do to try to prevent it. Some plants have even small sitting areas or arches. However, you need to be careful with your watering regime because too much or too little water can cause harm to your plants. You can also read our article, "5 Dangers To Overwatering A Cactus", to learn about all the possible dangers associated with excessive watering. These are typically USDA zones 9-11. If your region falls outside of these zones, don't be discouraged.